Environment files (.env) in Docker - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to load environment variables from a file named .env in Docker Compose.

Docker

services:
  app:
    env_file: [1]

Drag options to blanks, or click blank then click option'

Avariables.env

Bconfig.env

C.env

Denv.list

Attempts:

3 left

💡 Hint

Common Mistakes

Using a filename without the leading dot.

Confusing env_file with environment variables set directly.

The env_file option in Docker Compose specifies the file to load environment variables from. The default and common filename is .env.

2fill in blank

medium

Complete the .env file line to set the variable PORT to 8080.

Docker

PORT=[1]

Drag options to blanks, or click blank then click option'

A80

B8080

C8000

D443

Attempts:

3 left

💡 Hint

Common Mistakes

Adding quotes around the number.

Using a different port number.

In a .env file, variables are set as KEY=VALUE. To set PORT to 8080, write PORT=8080.

3fill in blank

hard

Fix the error in this .env line to correctly set the variable DEBUG to true.

Docker

DEBUG=[1]

Drag options to blanks, or click blank then click option'

Atrue

B"true"

CTRUE

DTrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using capitalized or quoted boolean values.

Leaving spaces around the equals sign.

In .env files, boolean values are usually lowercase without quotes. So DEBUG=true is correct.

4fill in blank

hard

Fill both blanks to create a .env line that sets the variable API_KEY to a secret value.

Docker

API_KEY=[1][2]

Drag options to blanks, or click blank then click option'

A12345

Babcdef

C"

D'

Attempts:

3 left

💡 Hint

Common Mistakes

Not using quotes for string values.

Using single quotes which may cause issues.

To set a string with letters in .env, wrap the value in double quotes: API_KEY="abcdef".

5fill in blank

hard

Fill all three blanks to write a Docker Compose environment section that uses the .env file and overrides PORT to 5000.

Docker

services:
  web:
    env_file: [1]
    environment:
      - PORT=[2]
      - DEBUG=[3]

Drag options to blanks, or click blank then click option'

A.env

B5000

Ctrue

Dfalse

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong filenames for env_file.

Setting PORT or DEBUG with wrong values or formats.

This Docker Compose snippet loads variables from .env and overrides PORT to 5000 and DEBUG to true in the environment section.